The town of Arcadia just got a good deal bigger without expanding a foot. Netflix has premiered the second series in Guillermo del Toro‘s Tales of Arcadia saga. And though 3Below may be a new show, it’s full of faces we already know.

Released in December of 2016, Trollhunters was the first installment of this multi-series story. It follows the story of Jim Lake (voiced by Anton Yelchin and then Emile Hirsch after Yelchin’s passing), a reluctant hero who becomes the first human Trollhunter. But Jim’s journey doesn’t just extend underground. With the premiere of 3Below, he’ll be tangentially connected to the stars. Here’s where you’ve seen 3Below‘s sweet, smart, and sassy royal family before and what their story might mean for this series’ future.

Where have we seen Aja and Krel before?

The royal siblings of Akiridion-5 made a guest appearance only the most dedicated fans likely remember. In Trollhunters Part 3, Jim gets in trouble for missing too many days of school. As punishment his principal Señor Uhl tasks him with guiding around the new kids — Aja and Krel. And that’s how a king and queen-in-waiting came to be part of a Trollhunting mission.

Though the episode doesn’t show off the pair’s alien forms, it does contain some fun moments. At one point Krel (voiced by Diego Luna) shows off his dance moves to his new friends, and Aja (voiced by Tatiana Maslany) helps our heroes navigate the stars in their quest from Merlin. The episode ends with a successful mission. As Jim and his friends walk away with the captured lightning, Aja and Krel say goodbye and return home.

Do Trollhunters characters appear in 3Below?

Absolutely. After all Jim, Charlie (voiced by Charlie Saxton), and Claire (voiced by Lexi Medrano) all go to the same school as Aja and Krel. There are lots of references to Trollhunters throughout the new series, but if you’re in the mood for a full-on crossover check out “D’aja Vu.” In the episode a giant troll attacks the school, threatening to expose both the troll world as well as Aja and Krel’s secret identities.

What could happen in 3Below Part 2?

The first season of the alien epic ends with the Zeron Brotherhood attacking Aja, Krel, and their guardian Varvatos Vex (voied by Nick Offerman). After several high-stakes battles, our heroes finally win. But in the waning moments of their victory something terrible happens — a human takes a picture of the alien siblings out of their disguises. If another season happens it will likely explore Aja and Krel trying to justify or explain away their identities. We’re rooting for you crazy kids!